Buddy I know that all. I am a android developer myself.
Right now glasswire doesn't enforce the firewall like on Windows and it has to keep track of each and every byte of data spent on mobile. The way it works now on my mobile there is no way its tracking anything.
It works while app is open. but once in background, nothing.
And this is not about only my phone but all the vivo phones out their with horrible funtouch ROM
I asked many of my friends (rather forced them) to install glasswire but the way it doesn't work, many of them uninstalled.
This app should have same or even more priority then any stupid system activity that runs in background because i can say that stupid google play services is not useful to me but GlassWire is way way more to me.
Right now its totally useless to me and with heavy heart i have to uninstall even though i am its biggest fan.
Unless i root my phone i cant even disable the Clean Master. SOB Vivo has seen to it. And i know what its doing to me aside from being a Chinese data stealing malware adware crap
Hope you implement something in future @Ken_GlassWire